Documentation

shell - Execute commands in nodes.

Synopsis

  • The shell module takes the command name followed by a list of space-delimited arguments. It is almost exactly like the command module but runs the command through a shell (/bin/sh) on the remote node.
  • For Windows targets, use the win_shell module instead.

Parameters

Parameter
Choices/Defaults
Comments
chdir
cd into this directory before running the command
creates
a filename, when it already exists, this step will not be run.
executable
change the shell used to execute the command. Should be an absolute path to the executable.
free_form
required
The shell module takes a free form command to run, as a string. There's not an actual option named "free form". See the examples!
removes
a filename, when it does not exist, this step will not be run.
stdin
(added in 2.4)
Set the stdin of the command directly to the specified value.
warn
(added in 1.8)
    Choices:
  • no
  • yes ←
if command warnings are on in ansible.cfg, do not warn about this particular line if set to no/false.

Notes

Note

  • If you want to execute a command securely and predictably, it may be better to use the command module instead. Best practices when writing playbooks will follow the trend of using command unless the shell module is explicitly required. When running ad-hoc commands, use your best judgement.
  • To sanitize any variables passed to the shell module, you should use “{{ var | quote }}” instead of just “{{ var }}” to make sure they don’t include evil things like semicolons.
  • For Windows targets, use the win_shell module instead.
  • Rather than using here documents to create multi-line scripts inside playbooks, use the script module instead.

Examples

- name: Execute the command in remote shell; stdout goes to the specified file on the remote.
  shell: somescript.sh >> somelog.txt

- name: Change the working directory to somedir/ before executing the command.
  shell: somescript.sh >> somelog.txt
  args:
    chdir: somedir/

# You can also use the 'args' form to provide the options.
- name: This command will change the working directory to somedir/ and will only run when somedir/somelog.txt doesn't exist.
  shell: somescript.sh >> somelog.txt
  args:
    chdir: somedir/
    creates: somelog.txt

- name: Run a command that uses non-posix shell-isms (in this example /bin/sh doesn't handle redirection and wildcards together but bash does)
  shell: cat < /tmp/*txt
  args:
    executable: /bin/bash

- name: Run a command using a templated variable (always use quote filter to avoid injection)
  shell: cat {{ myfile|quote }}

# You can use shell to run other executables to perform actions inline
- name: Run expect to wait for a successful PXE boot via out-of-band CIMC
  shell: |
    set timeout 300
    spawn ssh admin@{{ cimc_host }}

    expect "password:"
    send "{{ cimc_password }}\n"

    expect "\n{{ cimc_name }}"
    send "connect host\n"

    expect "pxeboot.n12"
    send "\n"

    exit 0
  args:
    executable: /usr/bin/expect
  delegate_to: localhost

Return Values

Common return values are documented here, the following are the fields unique to this module:

Key
Returned
Description
cmd
string
always
The command executed by the task

Sample:
rabbitmqctl join_cluster rabbit@master
delta
string
always
The command execution delta time

Sample:
0:00:00.325771
end
string
always
The command execution end time

Sample:
2016-02-25 09:18:26.755339
msg
boolean
always
changed

Sample:
True
rc
int
always
The command return code (0 means success)

start
string
always
The command execution start time

Sample:
2016-02-25 09:18:26.429568
stderr
string
always
The command standard error

Sample:
ls: cannot access foo: No such file or directory
stdout
string
always
The command standard output

Sample:
Clustering node rabbit@slave1 with rabbit@master ...
stdout_lines
list
always
The command standard output split in lines

Sample:
["u'Clustering node rabbit@slave1 with rabbit@master ...'"]


Status

This module is flagged as stableinterface which means that the maintainers for this module guarantee that no backward incompatible interface changes will be made.

Support

For more information about Red Hat’s support of this module, please refer to this Knowledge Base article

Author

  • Ansible Core Team
  • Michael DeHaan

Hint

If you notice any issues in this documentation you can edit this document to improve it.